On Wed, 2020-01-08 at 16:45 +0200, Ville Syrjala wrote: > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > When moving the pipe disable & co. function calls from > haswell_crtc_disable() into the encoder .post_disable() hooks I > neglected to account for the MST vs. DDI interactions properly. > This now leads us to call these functions two times for the last > MST stream (once from the MST code and a second time from the DDI > code). The calls from the DDI code should only be done for SST > and not MST. Add the proper check for that. Oohh I forgot that too. > > This results in an MCE on ICL. My vague theory is that we turn off > the transcoder clock from the MST code and then we proceed to touch > something in the DDI code which still depends on that clock causing > the hardware to become upset. Though I can't really explain why > Stan's hack of omitting the pipe disable in the MST code would avoid > the MCE since we should still be turning off the transcoder clock. > But maybe there's something magic in the hw that keeps the clock on > as long as the pipe is on. Or maybe the clock isn't the problem and > we now touch something in the DDI disable code that really does need > the pipe to be still enabled. > > v2: Rebase to latest drm-tip > > Cc: José Roberto de Souza <jose.souza@xxxxxxxxx> > Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx> > Reported-by: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx> > Closes: https://gitlab.freedesktop.org/drm/intel/issues/901 > Fixes: 773b4b54351c ("drm/i915: Move stuff from > haswell_crtc_disable() into encoder .post_disable()") > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_ddi.c | 22 ++++++++++++---------- > 1 file changed, 12 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c > b/drivers/gpu/drm/i915/display/intel_ddi.c > index 07acd0daca25..6e0a75d1e6ca 100644 > --- a/drivers/gpu/drm/i915/display/intel_ddi.c > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c > @@ -3897,21 +3897,23 @@ static void intel_ddi_post_disable(struct > intel_encoder *encoder, > enum phy phy = intel_port_to_phy(dev_priv, encoder->port); > bool is_tc_port = intel_phy_is_tc(dev_priv, phy); > > - intel_crtc_vblank_off(old_crtc_state); > + if (!intel_crtc_has_type(old_crtc_state, INTEL_OUTPUT_DP_MST)) > { > + intel_crtc_vblank_off(old_crtc_state); > > - intel_disable_pipe(old_crtc_state); > + intel_disable_pipe(old_crtc_state); > > - if (INTEL_GEN(dev_priv) >= 11) > - icl_disable_transcoder_port_sync(old_crtc_state); > + if (INTEL_GEN(dev_priv) >= 11) > + icl_disable_transcoder_port_sync(old_crtc_state > ); > > - intel_ddi_disable_transcoder_func(old_crtc_state); > + intel_ddi_disable_transcoder_func(old_crtc_state); > > - intel_dsc_disable(old_crtc_state); > + intel_dsc_disable(old_crtc_state); > > - if (INTEL_GEN(dev_priv) >= 9) > - skl_scaler_disable(old_crtc_state); > - else > - ilk_pfit_disable(old_crtc_state); > + if (INTEL_GEN(dev_priv) >= 9) > + skl_scaler_disable(old_crtc_state); > + else > + ilk_pfit_disable(old_crtc_state); > + } Other option would be replace intel_dig_port->base.post_disable(&intel_dig_port->base, old_crtc_state, NULL); in intel_mst_post_disable_dp() by: intel_ddi_post_disable_dp(encoder, old_crtc_state, old_conn_state); if (INTEL_GEN(dev_priv) >= 11) icl_unmap_plls_to_ports(encoder); if (intel_crtc_has_dp_encoder(old_crtc_state) || is_tc_port) intel_display_power_put_unchecked(dev_priv, intel_ddi_main_link_aux_domain(dig_port)); if (is_tc_port) intel_tc_port_put_link(dig_port); I guess this goes more with changes that you did in the patch fixed. Anyway your changes looks good. Reviewed-by: José Roberto de Souza <jose.souza@xxxxxxxxx> > > /* > * When called from DP MST code: _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
